“Combining wireless communication, intelligent controls and light emitting diodes (LEDs), smart lamps offer end-users features like colour tuning, dimming, changing lighting scenes, remote control, motion sensing control, daylight control and other features. But these features require energy even when the lamps are not providing light, but are instead waiting for a wireless instruction from a smartphone or remote control unit. Tests conducted on a limited number of smart wireless LED lamps reveal that these products can have substantial standby power use – which, depending on hours of use, can even be higher than the energy consumed when the light is switched on.”

“Domestic light sources… typically operate 1-2 hours per day. The smart lamps producing 200 to 1000 lumens of light tested in this project had an average standby energy consumption representing 51 % of the total daily energy consumption when these lamps are operated one hour per day. That corresponds to an overall efficacy of 9 to 51 lumens per watt, meaning some smart lamps had the equivalent performance of incandescent lamps [16 lumens per watt]. If the lamps are switched on for two hours per day, standby energy represented 35 % and the efficacy is approximately 16 to 64 lumens per watt, much lower than the non-smart LED lamps already on the market today.”

Light-emitting diodes (LEDs) are advertised as environmentally friendly because they are energy efficient and mercury free. However, the material content of the LEDs, which generally include group III-V semiconductors, presents its own set of potential environmental impacts. The rapid growth in the LED industry implies that, ultimately, LEDs will contribute to the solid waste stream, and could impact resource availability, human health, and ecosystems in much the same way as generic electronic waste (e-waste) from computers and cell phones has generated concern in recent years.

“The growing number of digital billboards on U.S. roads and highways consume large amounts of energy and are creating a wide variety of electronic waste, according to a new report (pdf). The new study says the typical digital billboard consumes about 30 times as much energy as the average American household.”

“The digital billboards use more efficient LED (Light Emitting Diode) lighting than traditional signs, but deploy so many of the LED bulbs on each billboard that energy use is high; traditional billboards use just one or two large bulbs to illuminate signs. In addition, digital billboards are illuminated day and night, and require cooling systems that use more energy.”